On 8/5/20 5:29 AM, Richard W.M. Jones wrote:
VDDK plugin + --run was broken because of the following sequence of
events:

(1) After .config_complete, server redirects stdin/stdout to /dev/null.

(2) Server then calls vddk_get_ready which reexecs.

(3) We restart the server from the top, but with stdin/stdout
     redirected to /dev/null.  So saved_stdin/saved_stdout save
     /dev/null.

(4) run_command is called which "restores" /dev/null as stdin/stdout.

(5) The output of the --run option is sent to /dev/null.

In addition to fixing this problem with VDDK, it also makes general
sense not to redirect stdin/stdout before calling .get_ready since
this callback is supposed to be the last chance before the server
daemonizes, and redirecting stdin/stdout is part of daemonization.

It's been an interesting game of sequencing, but as we add more tests, we're certainly going to be more robust against future breakage ;)

Series looks good.

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org

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